f1chris writes: "GeoIQ by FortiusOne has just released the first version of their Javascript API, which allows mashup developers to include heatmap and other raster-based geoanalytics in their applications (you can read the full release announcement on the FortiusOne blog). You can signup for a free API key on the GeoIQ website.
We have a few example mashups up to give you an idea of what we're talking about (you can always see the full list in the "Demo Gallery" portion of the GeoIQ website):

NY vs. SF — compare census statistics in New York City and San Francisco and add points from a Yahoo! Local search into the analysis. For example: See how the two cities compare when it comes to finding single men or women in their 20s that make over $100k/yr that are also close to good bars (one of our favorites)